…and 60 years later, the paperback came out!
Douglas Menville and Robert Reginald edited a plup magazine called Forgotten Fantasy: Classics of Science Fiction and Fantasy, which survived for only about a year in 1970-71. However, it spawned the Newcastle Forgotten Fantasy Library series which reprinted 24 significant and difficult to find works of early fantasy, including five from William Morris (for details see: http://home.epix.net/~wallison/nffl.html). In 1975, Aladore was reprinted as the 5th volume in the series (Hollywood (Calif.) : Newcastle, 1975). The book says it is a reprint of the 1915 Dutton edition.
Robert Reginald founded Borgo Press in the same year, which published a hardcover edition of Aladore in 1980 (San Bernardino, Calif. : Borgo Press, 1980). This version states that it is a reprint of the 1975 Newcastle edition.
There is no written mention of any editing or scholarship going into the production of the various editions of Aladore. This does not mean the text was completely unchanged of course, but I don’t expect there to be much variation between the witnesses.